TOEFL - prefer large or small company? Large - stable jobs and fine salaries

Hi,all. This is my time controled toefl essay. Wondering if it contains severe mistakes or if it is too simple in vocabulary or structure. Need your help! Thanks!

Some people prefer to work for a large company. Others prefer to work for a small company. Which would you prefer? Use specific reasons and details to support your choice.

Large companies may provide us with stable jobs and fine salaries. However, as a young man who prefers challenge, I would rather choose a small comany as my beginning of career. A small company may increase my job abilities in a full scale, offer me precious experiences, and realize my dream of owning a company.

First of all, my abilities of working is fully developed in a small company. I may have to concern about all the business affairs in the company because the company doesn't have enough employees; during the course, I will get to know different parts of the working process. Suppose I'm working in a small factory, I will need to know details ranging from information of the sources of raw materials to product selling categories. No doubt these knowledge will help me a lot in my future career. However, I will need to concern much less in a large company which always contain many departments. If I am a sales manager in a large company, I will not necessarily concern other parts. So I will know less and be less competitive compared with those from small companies.

Moreover, more experiences are accumulated in small companies. For example, the success of KFC has always been considered a commercial mystery. It started from just a wayside fast food store and finally grew up into a worldwide company. The success may be related to the ideas the leaders came up with--to provide a most convenient and clean restaurant to the public. And the idea came from exactly their early selling experiences in the small store and the complaints of the customers then.

Last but not least, small companies will not always remain the same. With my effort, I believe I can turn the company into a large one. In small companies, I have more freedom to put my thoughts into action. For example, I may easily have the access to talk to the boss if any constructive idea jumps into my mind. Furthermore, it is more likely for me to be a leader myself in a small company than in a large one. And it is always my dream to own a business of my own.

In summary, of all the factors concerned above, I would rather take a small company as my choice where I can improve working abilities and experiences and finally fulfill my dream of a successful career.

Last but not least, small companies will not always remain the sameI think in this sentence you should contain a clearer reason why you'd rather take a small company. So that the first sentence can be the main idea of that paragraph.